Climate change and geographic barriers exacerbate the spread and threat of Psacothea hilaris (Pascoe, 1857) in China: Insights from ensemble model, geographic barrier simulations, and niche analysis

Climate change is a key driver affecting global ecosystems and biodiversity, particularly influencing the spread and distribution of forest pests in forest ecosystems. Psacothea hilaris (Pascoe, 1857), an important forestry pest, poses a serious threat to the mulberry industry and the health of forest ecosystems. This study integrated an ensemble model, geographic barrier analysis, and niche modelling to evaluate habitat suitability and future range shifts of P. hilaris under different climatic scenarios, and formulated corresponding prevention and control strategies. The results indicated that the ensemble model exhibited high accuracy (AUC = 0.97; TSS = 0.81). Mean diurnal range, precipitation seasonality, and precipitation of warmest quarter were the key drivers affecting the distribution of P. hilaris, and the response curves further revealed the existence of a non-linear pattern of these factors on its survival probability. Currently, P. hilaris is mainly distributed in central and southern China, while in the future, the area of its suitable habitat is expected to increase by 13.61 % to 64.04 %, and the centre of its distribution will move to higher latitudes. Multivariate environmental similarity surface (MESS) confirmed that the bioclimatic conditions in the future expansion area are highly similar to the current conditions. Moreover, the ecological niche overlap of P. hilaris will exceed 0.81 in the future periods. Additionally, topographic barriers did not significantly limit the dispersal ability of P. hilaris. This study not only provides data support for the development of refined control measures and ecological risk assessment for P. hilaris, but also provides valuable reference for the optimization of forest pest control strategies and ecosystem protection in China.